Graphene has garnered widespread interest for use in a number of applications due to its favorable mechanical and electronic properties. The electrical conductivity of graphene can be influenced by the amount and type of chemical functionalization on the graphene and the quantity of defects in the graphene basal plane. Although pristine graphene typically displays the highest electrical conductivity values, it can sometimes be desirable to tune the electrical conductivity and adjust the band gap. Tailoring of the band gap can be accomplished, for example, by introducing a plurality of defects (i.e., holes or perforations) within the graphene basal plane or increasing the number of such defects. The band gap can be influenced by both the size and number of holes present. Applications that have been proposed for graphene include optical devices, mechanical structures, and electronic devices. In addition to the foregoing applications, there has been some interest in perforated graphene for filtration applications, particularly single-layer perforated graphene.
Current techniques used to perforate CVD graphene include oxidation processes (e.g., UV ozone, plasma oxidation, and high temperatures), ion beams, template cutting (e.g., “cookie cutter” mechanical perforation), and direct synthesis using specialized growth substrates. However, these techniques are not presently suitable for large scale production of perforated graphene in commercially realistic quantities. Control of the pore size distribution and the number of pores per unit area can also be an issue. Production of sub-nanometer pores (<1 nm in pore size) can be particularly difficult to achieve.
Other two-dimensional materials having a thickness of a few nanometers or less and an extended planar lattice are also of interest for various applications. In an embodiment, a two dimensional material has a thickness of 0.3 to 1.2 nm. In other embodiment, a two dimensional material has a thickness of 0.3 to 3 nm. For example, molybdenum sulfide is a representative chalcogenide having a two-dimensional molecular structure, and other various chalcogenides can constitute the two-dimensional material in the present disclosure.
In view of the foregoing, techniques that allow pores to be produced in graphene with a desired pore density and pore size would be of considerable benefit in the art. The present disclosure satisfies this need and provides related advantages as well.